People spend a significant amount of time indoors, which has caused more concern about the quality of the air we breathe while inside buildings. Products and materials in homes and office buildings emit pollutants and chemicals, many of which may raise health concerns. Recent studies by the U.S. Environmental Protection Agency and other health agencies have shown that indoor air pollutants are typically two to five times (sometimes 10 to 100 times) higher than levels found in outside air. One class of pollutants that has come under particular scrutiny is volatile organic compounds (VOCs). These compounds are ubiquitous, and much attention has been given to identifying the source of VOCs and reducing their emissions.
Generally, VOCs that are particularly targeted for emission reduction are volatile compounds that contain the element carbon, excluding methane, carbon monoxide, carbon dioxide, carbonic acid, metallic carbides and carbonates, ammonium carbonate, and exempt compounds, such as methylene chloride and 1,1,1-trichlorethane. VOCs are emitted from a surprising number of articles used in everyday life, particularly from virtually all resin-based man-made materials. Thus, wallcovering materials, floorcoverings, ceiling tiles and so forth made from PVC all emit VOCs into the indoor environment. One known source of VOCs is products manufactured of polyvinyl chloride (PVC). Likewise, furniture made from particle board materials, which is wood based materials fixed in a resin binder system, also emit undesirable VOCs, particularly formaldehyde. Additional products utilize organic solvent components to obtain desired processing properties. For example, printing inks are applied using adhesion promoters and other adjuvants that are sources of VOCs in materials that are printed, such as wallpaper, furniture laminates, and the like.
Varnishes and coatings have been used previously to provide a protective finish over surfaces such as vinyl wallcoverings, floor products, furniture and printed articles. Examples of such products are described in U.S. Pat. No. 4,603,074. These overcoats provide protection against stains and damage, but are not designed to and do not reduce emission of VOCs to the environment.